Proto-Oncogenes and Oncogenes
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Published 2020-08-11
Most normal cells will undergo a programmed form of rapid cell death (apoptosis) when critical functions are altered and malfunctioning. Activated oncogenes can cause those cells designated for apoptosis to survive and proliferate instead.[3] Most oncogenes began as proto-oncogenes: normal genes involved in cell growth and proliferation or inhibition of apoptosis. If, through mutation, normal genes promoting cellular growth are up-regulated (gain-of-function mutation), they will predispose the cell to cancer; thus, they are termed "oncogenes". Usually multiple oncogenes, along with mutated apoptotic or tumor suppressor genes will all act in concert to cause cancer.
The proto-oncogene can become an oncogene by a relatively small modification of its original function. There are three basic methods of activation:
A mutation within a proto-oncogene, or within a regulatory region (for example the promoter region), can cause a change in the protein structure, causing
an increase in protein (enzyme) activity
a loss of regulation
An increase in the amount of a certain protein (protein concentration), caused by
an increase of protein expression (through misregulation)
an increase of protein (mRNA) stability, prolonging its existence and thus its activity in the cell
gene duplication (one type of chromosome abnormality), resulting in an increased amount of protein in the cell
A chromosomal translocation (another type of chromosome abnormality)
There are 2 different types of chromosomal translocations that can occur:
translocation events which relocate a proto-oncogene to a new chromosomal site that leads to higher expression
translocation events that lead to a fusion between a proto-oncogene and a 2nd gene (this creates a fusion protein with increased cancerous/oncogenic activity)
All Comments (21)
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The vid is very helpful! I hope you keep doing what you're doing. It's precise and straight to the point, just what I needed ^_^ I love your handwriting on the video, as well as the colored markers~ They add life to the vid, in my opinion.
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Ur explanations r so on point n easy to understand. Love ur work. Thank u so muchπ
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Thank you very much. You are doing a great job.
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Have you uploaded all the videos? I ain't able to find them.
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Simple and to the point Thanks
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Very lucid explanation. Thank you
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Just out of curiosity.. when you're making a video do you look up all the information in books/internet or is it all knowledge you already had?
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Amazing πππ
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excellent explanation but have some queries mutations theory how mutations take place first. like what is the source of mutagens. how nuclear DNA is getting mutated while it is highly protected because it is not free open molecule it is highly condensed farms chromatin. if you say its because of house keeping genes then tumor suppressor gene ( antioncogene ) do come under the category which could potentially inhibit the growth and leads to apoptosis. and prominent feature cancer is it loses the apoptosis. amplification yes this could be an issue but mostly sorted out by proofreading and repair mechanisms if not the cells enters pcd mode during check points in cell cycles chromosomal rearrangement but its extremely rare with frequency of 1 in 1000s or 10000s
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Nice video π
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Thank U!!
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Your video is too much informative thanx a lot, pls we want a video on field cancerization also because in article it is very much like round round imformation is given so my humble request for making a video on field cancerization pls
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Thanks sir!
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Thanks sir, please make a video on Bacteriophage lambda gene regulation
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Helpful
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Great effort Bro
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Tq u sir, u had cleared my doubt πππ
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Thanks from egypt country
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Videos is very informative and very easy. Sir plzzzzzz recommended any book for nucleic acid extraction.
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epic shit in 5 mins, great video man!